Matsya Purana — Genealogy and Classification of Sacred Fires
स मृतो ऽथर्वणः पुत्रो मथितः पुष्करोदधिः यो ऽथर्वा लौकिको ह्य् अग्निर् दक्षिणाग्निः स उच्यते //
sa mṛto 'tharvaṇaḥ putro mathitaḥ puṣkarodadhiḥ yo 'tharvā laukiko hy agnir dakṣiṇāgniḥ sa ucyate //
That son of Atharvan—called Puṣkarodadhi—who was produced by churning and then died: the Atharvanic fire used in worldly rites is said to be the Dakṣiṇāgni, the southern sacred fire.
It does not discuss Pralaya; it defines the Dakṣiṇāgni by linking it to an Atharvanic, ‘worldly’ fire tradition and a named figure (Puṣkarodadhi) produced by churning.
By identifying Dakṣiṇāgni as the laukika (practical/household) Atharvanic fire, it supports correct performance of domestic and public rites—an essential duty for householders and for kings who sponsor sacrifices.
Ritually, it clarifies the identity of Dakṣiṇāgni among the sacred fires and associates it with fire produced by friction (arani-churning), guiding correct setup and usage in yajña procedures.